Calling to a constructor with promoted properties has side effects

Author: ondrejmirtes

Diff for: src/Analyser/MutatingScope.php

@@ -2969,6 +2969,7 @@ public function enterClassMethod(
 		array $parameterOutTypes = [],
 		array $immediatelyInvokedCallableParameters = [],
 		array $phpDocClosureThisTypeParameters = [],
+		bool $isConstructor = false,
 	): self
 	{
 		if (!$this->isInClass()) {
@@ -2999,6 +3000,7 @@ public function enterClassMethod(
 				array_map(fn (Type $type): Type => $this->transformStaticType(TemplateTypeHelper::toArgument($type)), $parameterOutTypes),
 				$immediatelyInvokedCallableParameters,
 				array_map(fn (Type $type): Type => $this->transformStaticType(TemplateTypeHelper::toArgument($type)), $phpDocClosureThisTypeParameters),
+				$isConstructor,
 			),
 			!$classMethod->isStatic(),
 		);

Diff for: src/Analyser/NodeScopeResolver.php

@@ -614,6 +614,9 @@ private function processStmtNode(
 				$nodeCallback($stmt->returnType, $scope);
 			}
 
+			$isFromTrait = $stmt->getAttribute('originalTraitMethodName') === '__construct';
+			$isConstructor = $isFromTrait || $stmt->name->toLowerString() === '__construct';
+
 			$methodScope = $scope->enterClassMethod(
 				$stmt,
 				$templateTypeMap,
@@ -632,14 +635,14 @@ private function processStmtNode(
 				$phpDocParameterOutTypes,
 				$phpDocImmediatelyInvokedCallableParameters,
 				$phpDocClosureThisTypeParameters,
+				$isConstructor,
 			);
 
 			if (!$scope->isInClass()) {
 				throw new ShouldNotHappenException();
 			}
 
-			$isFromTrait = $stmt->getAttribute('originalTraitMethodName') === '__construct';
-			if ($isFromTrait || $stmt->name->toLowerString() === '__construct') {
+			if ($isConstructor) {
 				foreach ($stmt->params as $param) {
 					if ($param->flags === 0) {
 						continue;

Diff for: src/Reflection/Php/PhpMethodFromParserNodeReflection.php

@@ -60,10 +60,14 @@ public function __construct(
 		array $parameterOutTypes,
 		array $immediatelyInvokedCallableParameters,
 		array $phpDocClosureThisTypeParameters,
+		private bool $isConstructor,
 	)
 	{
 		$name = strtolower($classMethod->name->name);
-		if (in_array($name, ['__construct', '__destruct', '__unset', '__wakeup', '__clone'], true)) {
+		if ($this->isConstructor) {
+			$realReturnType = new VoidType();
+		}
+		if (in_array($name, ['__destruct', '__unset', '__wakeup', '__clone'], true)) {
 			$realReturnType = new VoidType();
 		}
 		if ($name === '__tostring') {
@@ -175,6 +179,11 @@ public function isAbstract(): TrinaryLogic
 		return TrinaryLogic::createFromBoolean($this->getClassMethod()->isAbstract());
 	}
 
+	public function isConstructor(): bool
+	{
+		return $this->isConstructor;
+	}
+
 	public function hasSideEffects(): TrinaryLogic
 	{
 		if (

Diff for: src/Rules/DeadCode/ConstructorWithoutImpurePointsCollector.php

@@ -7,7 +7,6 @@
 use PHPStan\Collectors\Collector;
 use PHPStan\Node\MethodReturnStatementsNode;
 use function count;
-use function strtolower;
 
 /**
  * @implements Collector<MethodReturnStatementsNode, string>
@@ -23,7 +22,7 @@ public function getNodeType(): string
 	public function processNode(Node $node, Scope $scope)
 	{
 		$method = $node->getMethodReflection();
-		if (strtolower($method->getName()) !== '__construct') {
+		if (!$method->isConstructor()) {
 			return null;
 		}
 

Diff for: src/Rules/DeadCode/MethodWithoutImpurePointsCollector.php

@@ -49,11 +49,7 @@ public function processNode(Node $node, Scope $scope)
 			return null;
 		}
 
-		$declaringClass = $method->getDeclaringClass();
-		if (
-			$declaringClass->hasConstructor()
-			&& $declaringClass->getConstructor()->getName() === $method->getName()
-		) {
+		if ($method->isConstructor()) {
 			return null;
 		}
 

Diff for: src/Rules/Pure/FunctionPurityCheck.php

@@ -40,18 +40,11 @@ public function check(
 		array $impurePoints,
 		array $throwPoints,
 		array $statements,
+		bool $isConstructor,
 	): array
 	{
 		$errors = [];
 		$isPure = $functionReflection->isPure();
-		$isConstructor = false;
-		if (
-			$functionReflection instanceof ExtendedMethodReflection
-			&& $functionReflection->getDeclaringClass()->hasConstructor()
-			&& $functionReflection->getDeclaringClass()->getConstructor()->getName() === $functionReflection->getName()
-		) {
-			$isConstructor = true;
-		}
 
 		if ($isPure->yes()) {
 			foreach ($parameters as $parameter) {

Diff for: src/Rules/Pure/PureFunctionRule.php

@@ -36,6 +36,7 @@ public function processNode(Node $node, Scope $scope): array
 			$node->getImpurePoints(),
 			$node->getStatementResult()->getThrowPoints(),
 			$node->getStatements(),
+			false,
 		);
 	}
 

Diff for: src/Rules/Pure/PureMethodRule.php

@@ -36,6 +36,7 @@ public function processNode(Node $node, Scope $scope): array
 			$node->getImpurePoints(),
 			$node->getStatementResult()->getThrowPoints(),
 			$node->getStatements(),
+			$method->isConstructor(),
 		);
 	}
 

Diff for: tests/PHPStan/Rules/DeadCode/CallToMethodStatementWithoutImpurePointsRuleTest.php

@@ -72,6 +72,14 @@ public function testBug11011(): void
 		]);
 	}
 
+	public function testBug12379(): void
+	{
+		if (PHP_VERSION_ID < 80000) {
+			$this->markTestSkipped('Test requires PHP 8.1.');
+		}
+		$this->analyse([__DIR__ . '/data/bug-12379.php'], []);
+	}
+
 	protected function getCollectors(): array
 	{
 		return [

Diff for: tests/PHPStan/Rules/DeadCode/data/bug-12379.php

@@ -0,0 +1,22 @@
+<?php // lint >= 8.1
+
+namespace Bug12379;
+
+class HelloWorld
+{
+	use myTrait{
+		myTrait::__construct as private __myTraitConstruct;
+	}
+
+	public function __construct(
+		int $entityManager
+	){
+		$this->__myTraitConstruct($entityManager);
+	}
+}
+
+trait myTrait{
+	public function __construct(
+		private readonly int $entityManager
+	){}
+}